(141c) Layered Hybrid Structure of Cobalt/N-Doped Carbon Derived from Metal-Organic Frameworks for Electrocatalytic Hydrogen Evolution

This study reports in situ synthesis of Co/N-Carbon hybrid structures via the pyrolysis of layered cobalt based metal–organic frameworks. As excellent hydrogen evolution reaction (HER) catalysts, the 2D hybrid layered structure composed by ultrafine metallic cobalt nanoparticles and N-carbon, showed a small overpotential of 103 mV (vs RHE) at 10mA/cm2, high cycle durability and considerable long-term stability for HER. The superior electrochemical performances of Co/N-carbon for HER can be attributed to such 2D configuration which includes the low H atom binding energy of metallic cobalt, the high conductivity of carbon and the stability of carbon-encapsulated Co nanoparticles. Therefore, we have worked on the synthesis and characterization of the 2D hybrid structure of Co/N-Carbon derived from metal organic frameworks. The as-prepared 2-D sheet structures retained the well-defined morphology of the initial Co-based MOFs, and cobalt nanoparticles (ca. 7.2 nm) were well embedded on the N-carbon. Due to the integration of the superior features of ultrafine cobalt nanoparticles and N-carbon, the resultant Co/N-Carbon showed enhanced electrocatalytic activity and durability when compared to the commercial Pt/C electrocatalyst at the alkaline media. More importantly, Co/N-carbon’s electrocatalytic activities in terms of overpotential at 10mA/cm2 for hydrogen evolution have been more advantageous over other nanocarbon-based electrocatalysts.

Acknowledgements: Financial support from Interdisciplinary Graduate School, Nanyang Technological University Singapore is gratefully acknowledged.

References

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